A transparent laminate is known, which is produced by laminating a pair of transparent substrates via a thermoplastic resin film of e.g. polyvinyl butyral (PVB) or a thermocrosslinkable transparent resin film while the transparent substrates are heated and pressurized by an autoclave, and when the transparent substrates are glass substrates, the laminate is known by the name of laminated glass. Such a laminated glass is used as a windshield glass for automobiles since it has a merit that fragments of broken glass are adhered to the film without scattering, and it is also used as a window glass (safety glass or security glass) of buildings since it is hard to be penetrated and is excellent in strength.
However, in terms of the process for producing the transparent substrate using the above mentioned transparent resin film, there are such problems that a high temperature environment of at least 70° C. or at least 120° C. is required and that since a high pressure of at least 10 atm is required, the production presents a major impact on the environment. Further, for the same reason, there is also a problem that a transparent substrate easily deformable by heat, such as a transparent resin substrate, cannot be used as the transparent substrate. Further, there is also a problem that when a transparent resin film is cut into a size of the transparent substrate, since trimmed films are wasted as unnecessary films, utilization efficiency of the transparent resin film is poor.
As a process for producing laminated glass solving these problems, a process disclosed in e.g. Patent Document 1 is known. In this process, first, a plate-shaped container constituted by a pair of glass substrates laminated via an adhesive spacer is produced, and next, a part of the spacer is opened, a curable resin composition is injected through the opening portion, and subsequently, the opening portion of the spacer is plugged to be closed, and the curable resin composition is cured by heating (including long time preservation at a room temperature) or exposure to UV rays, to produce a laminated glass (hereinafter this method is referred to as injection method). Accordingly, according to this process, since no high temperature environment or high pressure environment is required, it is possible to use a transparent substrate easily deformable by heat, and since no transparent resin film is used, it is possible to save a resource.    Patent Document 1: JP-A-2005-41747